World time clock system



Oct. 14, 1969 H. KARAKAWA WORLD TIME CLOCK SYSTEM 2 Sheets-Sheet 1 Filed April 6, 1967 INVENTOR. fW/ME A 4Q4/(4W4 an /W Oct. 14, 1969 H. KARAKAWA WORLD TIME CLOCK SYSTEM 2 Sheets-Sheet Filed April 6. 1967' IIIIIIIIA 'll fill! mmlllllm mm] IILIII un-I" Fun-n United States Patent 3,472,021 WORLD TIME CLOCK SYSTEM Hajime Karakawa, PO. Box 335, Makawao, Hawaii 96768 Filed Apr. 6, 1967, Ser. No. 628,928

Int. Cl. G041) 19/22 US. CI. 58-43 1 Claim ABSTRACT OF THE DISCLOSURE A world time clock system having a 24-hour clock, which may be a one revolution per 12-hour movement clock with reducing means to halve the rotation to that of a 24-hour movement clock per one revolution, and by adding a zone disc which is driven by the hour hand, the hour hand being thus eliminated. By driving the zone disc around the clock face a complete turn in one 24- hour day, it is apparent what the actual time is in hours for any particular zone of interest, as well as the mmutes and seconds, which hands are also provided and driven by the clock mechanism. The dial of the clock contains the numbers of the hours and identification of day and night, or A.M. and P.M., in fixed relation, while the zone dial is radially disposed therewith and rotates about 1t as described above.

The present invention relates to an improved world time clock showing 24-hour movement throughout a single revolution of the zone disc or hour indicator means, and more particularly the invention relates to a mechanism that can be used to reduce the hour hand rotatron of once in 12-hour movement to once in a 24-hour period, and by attaching a zone disc adjacent a numbered face so that the time in hours and minutes at any one particular zone may be readily determined by a single 1nstrument. I

A further object and advantage of the invention 1s to enable one to become knowledgeable of the time throughout the world any day or night so that the time of a particular place in any given time zone may be read1ly determined.

Another object of the invention is to provide a device that is easily manufactured with slight additional cost to present clock structures to provide the usefulness and advantages as set forth above.

The above and other objects and advantages will become apparent upon full consideration of the following detailed description and accompanying drawings in which:

FIGURE 1 is a front elevation view with a portion thereof broken away and illustrating the salient features of the invention;

FIGURE 2 is a cross-sectional view taken along lines 2--2 of FIGURE 1.

Referring now to the drawings, there is shown a basic or conventional 12-hour clock having a wall plate 12 for it to be mounted on a. wall or other vertical structure, and in which the clock movement provides one rotation of the hour hand for any 12-hour period. A spindle shaft 14 inserted within spindle shaft 16 is provided to indicate seconds and minutes on the face of the clock in conventional rotation of the second hand 20 and the minute hand 22, as seen in FIG. 1. There is also provided in concentric rotation with spindles 14, 16, an outside shaft 26 which is driven by a further reducing mechanism 28 so that the shaft 26 provides one rotation in a period of 24 hours in lieu of the 12-hour period. The gear 30 is seen to drive the shaft 26 and a bearing 32 is provided to seal the enclosure of the clock 10. The shaft 26' is secured to a flange 34 which in turn supports the zone disc 38 which may be made of plastic or other material adaptable for receiving decals or other indicia thereon. Screws 40, 42 are provided to secure the flange 34 to the zone disc 38.

Behind the zone disc 38 and mounted for adjustably fixed positioning, there is a circular 24-hour clock face 40 which may be readily observed through the transparent zone disc 38. The zone disc 38 revolves around the clock face for a complete turn in one 24-hour day, and there is disposed on the zone disc indicia indicative of the respective zones throughout the world between 0 longitudinal and longitude both East and West. The zone disc indicates the hours that are passing through the zones, while the second and minute hands indicate the correct portions of the hour of each such zone.

The time is set by first getting the correct time of the zone where the clock is positioned and aligning the hour number with the zone disc. For instance, since the clock 10 is in a given zone, the clock face 40 is rotated until it is in proper alignment to indicate the correct time to the zone where the clock 10 is. After the correct setting, all the rest of the zones will have the proper time capable of being identified or indicate-:1. Also substitute or replacement daylight indicia decals for the indicia decals 48, 50 may be replaced to indicate daylight time in those zones that are characterized by daylight saving. By means of the clock of the present invention, it is possible to perceive that part of the world that is in daylight and night, as well as that part which is in daylight saving time, as described above. The clock of the present invention shows how and when the calendar day changes take place and also the function of the international date line which is disclosed and made part of FIG. 1.

While some airports and other facilities have two dozen clocks for each of the time zones and cities of such time zones, it is seen by the apparatus of the present invention that one can obtain all the time zone information for any given time zones as well as for a given city or country, as well as the day and night periods thereof all from a single instrument. The clock is useful for understanding present day rapid transportation on land, sea and air when traveling to different time zones and across the international date line.

What is claimed is:

1. A world time clock apparatus having a conventional mechanism in which there is one revolution of the hour hand per 12-hour movement thereof, the improvement thereof consisting in reducing means to halve the rotation of the hour hand to a 24-hour movement clock, the minute hand of said clock mechanism disposed within a concentric hollow shaft, said concentric hollow shaft being driven by said 24-hour movement means, said concentric hollow shaft driving a zone disc, said zone disc having indicia of the 24 time zones throughout the world indicative of the times thereof, a face plate for said clock mechanism, and indicia decals may be replaced by daylight indicia decals to indicate daylight saving time in those zones that are characterized by daylight saving time, the rotating zone disc being superimposed over a clock face which indicates the portions of the hours that are indicated on the zone disc.

References Cited UNITED STATES PATENTS 2,056,038 9/1936 Angelis et al. 5-8-43 2,641,898 6/1953 Galley 58-43 3,049,863 10/1962 Ranney 5844 3,091,915 6/1963 Pawl 5850 RICHARD B. WILKINSON, Primary Examiner E. C. SIMMONS, Assistant Examiner 

